{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/the-stellar-mass-physical-effective-radius","title":"The stellar mass - physical effective radius relation for dwarf galaxies in low-density environments","arxiv_id":"2106.14924","date":"2021-06-28","proceeding":null,"authors":["Daniel J. Prole"],"abstract":"The scaling relation between stellar mass ($M_{*}$) and physical effective radius ($r_{e}$) has been well-studied using wide spectroscopic surveys. However, these surveys suffer from severe surface brightness incompleteness in the dwarf galaxy regime, where the relation is poorly constrained. In this study, I use a Bayesian empirical model to constrain the power-law exponent $\\beta$ of the $M_{*}$-$r_{e}$ relation for late-type dwarfs ($10^{7}$$\\leq$$M_{*}$/$M_{\\odot}$$\\leq$$10^{9}$) using a sample of 188 isolated low surface brightness (LSB) galaxies, accounting for observational incompleteness. Surprisingly, the best-fitting model ($\\beta$=0.40$\\pm$0.07) indicates that the relation is significantly steeper than would be expected from extrapolating canonical models into the dwarf galaxy regime. Nevertheless, the best fitting $M_{*}$-$r_{e}$ relation closely follows the distribution of known dwarf galaxies. These results indicate that extrapolated canonical models over-predict the number of large dwarf (i.e. LSB) galaxies, including ultra-diffuse galaxies (UDGs), explaining why they are over-produced by some semi-analytic models. The best-fitting model also constrains the power-law exponent of the physical size distribution of UDGs to $n\\mathrm{[dex^{-1}]}\\propto$$~r_{e}^{3.54\\pm0.33}$, consistent to within 1$\\sigma$ of the corresponding value in cluster environments and with the theoretical scenario in which UDGs occupy the high-spin tail of the normal dwarf galaxy population.","url_abs":"https://arxiv.org/abs/2106.14924v1","url_pdf":"https://arxiv.org/pdf/2106.14924v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"the-stellar-mass-physical-effective-radius","repo_url":"https://github.com/danjampro/udg-sizes","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}